Biometric data generally holds a wealth of unique identifying information that may be used in a variety of different ways, with security applications being a common use of biometric data. This is due, in part to the fact that biometric data is not easily counterfeited and is uniquely associated with a person. Fingerprint and retina recognition devices, for example, are relatively common biometric data collecting devices that are used to collect biometric data for security purposes.
A common approach to fingerprint identification involves scanning a sample fingerprint or an image thereof and storing the image and/or unique characteristics of the fingerprint image. The characteristics of a sample fingerprint may be compared to information for reference or enrolled fingerprints already in a database to determine proper identification of a person, such as for verification purposes. In some instances, a fingerprint recognition device may scan only a section of a fingerprint. The fingerprint recognition device can collect the fingerprint image sections to form a template of the fingerprint. Some systems store multiple templates for each user to account for different fingerprints and variations in the fingerprints.
After a template is enrolled for a given user, however, the skin on a user's finger can change over time which can make it difficult to match newly captured fingerprint images (or fingerprint image sections) with the enrolled template. For example, a portion of the skin on a finger can develop a callus over time that adversely affects the fingerprint matching process. Depending on the size and thickness of the callus, the fingerprint recognition device may not be able to match a recently captured fingerprint image or fingerprint image section with the template for that finger. Alternatively, the skin on a user's finger may have a normal moisture level when the template for that finger is enrolled with the fingerprint recognition device. Over time, however, the user's skin may become drier, which can make it more difficult to match a newly captured fingerprint image with the enrolled template for that finger.